Apparatus for loading and baling crop material

ABSTRACT

In a baling operation that uses a continuously reciprocating plunger, if the next charge to be stuffed into the chamber has not yet reached the desired size and density by the time the stuffing fork is ready to begin its next operating cycle, the fork is temporarily deactivated, without affecting the plunger, until the charge reaches full size and density. Thereupon, the fork stuffs the entire charge into the baling chamber in a single cycle of operation for compaction by the plunger. The baler is loaded from the bottom of the baling chamber through an upwardly curved duct that serves both as an accumulating chamber and as a precompression area into which the charge is progressively packed by a rotating, retractable finger drum at the lower end of the duct. A backstop for precompression purposes may be presented at the top of the duct in a number of alternative ways, i.e., the moving plunger itself may be of such length as to cover the duct during a large portion of its stroke; the stuffing fork may be stopped at a position within and extending across the duct; or an auxiliary device may be rocked into and out of the duct in timed relation to operation of the fork.

This is a division of application Ser. No. 737,472 filed on Nov. 1, 1976now U.S. Pat. No. 4,106,268.

This invention relates to balers of the type described and claimed inco-pending applications for U.S. Letters Patents, Ser. No. 675,475,filed Apr. 9, 1976, in the names of VOTH, et al, and titled "CROPDENSITY SENSING MECHANISM FOR BALER LOADING APPARATUS", and Ser. No.675,529, filed Apr. 9, 1976, in the name of ALLEN WHITE, and titled"BALER LOADING METHOD AND APPARATUS." The foregoing applications and thepresent invention are commonly owned by the assignee of the presentinvention.

The aforesaid applications relate at least in part to a majorbreakthrough in the "packaging" of hay and other crop materials. Whilethe principles described and claimed in the application have utility inthe production of small bales on the order of 60 to 100 pounds, theyhave perhaps the greatest impact in the preparation of massive, highlydense bales on the order of one ton or more. As was pointed out in theapplications, a principal obstacle in the production of such balesinvolves the inability of conventional mowing, raking, conditioning andwindrowing equipment to prepare sufficiently voluminous and uniformwindrows that the spacious baling chamber of the machine making thelarge bales can be loaded with uniformly dense, precisely sized chargesthat occupy the entire charging space of the chamber.

One way of overcoming this obstacle, as explained in the aforesaidapplications, is to interrupt the otherwise continuously repetitiousloading and compacting cycles long enough to accumulate a supply orcharge of material that precisely meets the predetermined standards forsuch charges. Only after precisely the proper charge has beenaccumulated in an auxiliary chamber of the machine is that charge thenbriskly stuffed into the bale chamber by the reactivated loader andcompacted against previously loaded material by the re-energizedplunger.

Temporarily halting both the plunger and the loader while pickup andaccumulation of a perfect charge continue on a non-stop basis becomesprogressively more difficult as the operating speeds of the plunger andloader are increased in order, for example, to increase the capacity ofthe machine. Starting and stopping the plunger with its great mass in asuitably abrupt manner can severely tax the clutching apparatus used toeffect such stopping and starting, and thereby contribute to the earlyfailure of such mechanical components.

On the other hand, the concept of accumulating picked up crop materialuntil such time as a perfectly shaped and uniformly dense charge isobtained and only then stuffing the same into the bale chamber remainsan extremely attractive and viable solution to the aforementionedproblems of windrow size and consistency. Accordingly, one importantobject of the present invention is to offer an alternative to clutchingboth the plunger and the loader through the provision of a method andapparatus that involves operating the plunger on a continuouslyreciprocating basis and clutching only the loader to temporarilydeactivate the same if the charge accumulating during the precedingloading stroke does not meet predetermined standards of size anddensity. In other words, the present invention contemplates operatingthe plunger on a non-stop basis yet deactivating the loader to skip oneor more plunger strokes until such time as the accumulating chargereaches the desired parameters of density and size, at which time theloader is reactivated in synchronism with the plunger.

Another important object of the present invention is to provide forprecompression of the accumulating charge prior to stuffing the sameinto the bale chamber notwithstanding the continuous reciprocation ofthe plunger. In this respect, alternative arrangements are provided forutilizing the continuously moving plunger itself as a backstop for suchprecompression, utilizing the stuffer-loader as a backstop byterminating its stroke while the latter remains at one end of theaccumulation chamber, or inserting an auxiliary backstop device into theaccumulating chamber in timed relationship to operation of the loader.

A still further important object of this invention is to provide a wayof maintaining reciprocation of the plunger, operation of the loader andactuation of the auxiliary backstop device all in properly timedrelationship to one another notwithstanding the continuous operation ofcertain of the components and the intermittent operation of others.

In the drawings:

FIG. 1 is a fragmentary, elevational view of the left side of a balerconstructed in accordance with the principles of the present inventionand capable of carrying out our novel method;

FIG. 2 is a fragmentary, elevational view of the right side thereof,parts being broken away and shown in cross section for clarity;

FIg. 3 is a substantially vertical cross-sectional view of the balertaken along line 3--3 of FIG. 2;

FIG. 4 is an enlarged diagrammatic view of the loader and its associatedapparatus illustrating the relationship between the same at variousstages in the loading and baling cycles;

FIG. 5 is an enlarged, substantially horizontal cross-sectional view ofthe loader and its associated apparatus looking downwardly from aposition just below the bale case of the machine, the stuffing forks ofthe loader being illustrated in the 120° position of FIG. 4;

FIG. 6 is an enlarged, fragmentary elevational view of the clutch forthe loader, the clutch being illustrated in a tripped or engagedposition immediately following actuation of the loader;

FIG. 7 is a diagrammatic view somewhat similar to FIG. 4, butillustrating an alternative arrangement for stopping the fork of theloader within the loading duct to serve as a backstop for precompressionof accumulating material;

FIG. 8 is an edge elevational view of the clutch utilized in thearrangement of FIG. 7; and

FIG. 9 is a side elevational view thereof illustrating the position ofthe clutch at a point fully within the operating cycle.

The baler has a long fore-and-aft extending hole case 10 of rectangularcross section that defines a baling chamber denoted by the numeral 12 inFIGS. 4 and 7. The bale case 10 is supported in a slightly upwardly andforwardly inclined manner by struts 14 having ground-engaging wheels 16at their lowermost ends, and a downwardly and forwardly projectingtongue 18 at the front of the bale case 10 is adapted for hitching thebaler to a towing vehicle (not shown) for advancing the same across afield. An enclosed plunger 20 reciprocates continuously fore-and-aftwithin chamber 12 for compacting material presented to the chamber 12through an inlet 22 in the floor 24 of bale case 10 across the fullwidth thereof.

An upwardly curved loading duct 26 depends from the bale case 10 and hasits upper discharge end 28 in registration with the inlet 22, while thelower receiving end 30 of the duct is remote from inlet 22 and isdisposed substantially forwardly thereof. Duct 26 flares outwardly in afore-and-aft direction as its upper end 28 is approached and defines aslightly wedge-shaped chamber 27. The curved top wall 32 of the duct 26is provided with laterally spaced, longitudinal slots 34 extending thefull length thereof, while the curved bottom wall 36 of the duct 26 issolid over its entire length except for the area immediately adjacentthe bale case 10 which is longitudinally slotted to accommodate anauxiliary backstop device 38 yet to be described.

The lower end 30 of the duct 26 is positioned directly behind a croppickup 40 which may be of any design capable of picking up windrowedmaterials from the field and delivering the same rearwardly into theduct 26. In the illustrated embodiment, the pickup 40 has a series oflifting tines 42 that sweep the crop upwardly to an overhead auger 44which gathers the crop centrally and delivers it rearwardly into the end30 of the duct 26.

A rotary packer 46 is located between the pickup 40 and the duct 26 andacross end 30 of the latter for making a precompressed charge ofmaterial within the duct 26 preparatory to loading the baling chamber12. As illustrated, the top wall 32 of duct 26 terminates in rearwardlyspaced relationship to the forward termination of the bottom wall 36,and the fore-and-aft space defined between such forward terminations isoccupied by the packer 46. The latter includes a hollow drum 48 that issupported for rotation above the bottom wall 36 in the area of itsupward curvature adjacent end 30, but the vertical distance between thebottom wall 36 and the periphery of the drum 48 at that location issubstantially less than the corresponding dimension of the duct 26throughout the remainder of its length to the bale case 10. Accordingly,the collecting chamber 27 of the duct 26 is constricted in the areaimmediately below the packer 46 which enables the rear periphery of thedrum 48 to prevent retrograde movement of the material being packed intochamber 27 as will subsequently become clear.

The packer 46 also includes a plurality of crop-engaging fingers 50which project radially from the axis of rotation of drum 48 and aredisposed about the latter in relatively closely spaced pairs asillustrated in FIG. 5. To carry out the desired packing action and yeteffectively withdraw from the crop materials, the fingers 50 are mountedwithin the drum 48 in such a way as to be extended as the drum 48rotates down into the crop and retracted as the drum rotates up and outof the crop past the top wall 32 of duct 26. This action per se is notnew and may be accomplished using mechanism such as described in U.S.Letters Patent, 2,748,921, owned by the assignee of the presentinvention. Briefly, for purposes of a full understanding of the presentinvention, suffice it to say that the mechanism for extending andretracting the fingers 50 includes a stationary shaft 52 extending thelength of drum 48 in coaxial relationship therewith. A pair ofstationary cranks 54 (one only being shown) at opposite ends of theshaft 52 are rigidly affixed to the latter and cooperate to support asecond shaft 56 in radially spaced, parallel relationship with the shaft52. Spaced along the shaft 56 are a number of elongated mounts 58, eachwhich has a longitudinal trackway 60 within which a roller 62 on shaft56 can operate, and each of the mounts 58 carries two oppositelyextending pairs of the fingers 50. Thus, when the drum 48 is rotated,the fingers 50 and mounts 58 are carried around the axis of shaft 56which, by its eccentric relationship to the axis of rotation of the drum48, causes the mounts 58 to move back and forth on rollers 62 andthereby retract and extend the fingers 50, respectively.

An elongated scraper blade 64, mounted on the top wall 32, extendsacross the full width of the duct 26 in close proximity to the peripheryof drum 48 for wiping crop material which might otherwise cling to thedrum 48 during its rotation past the top wall 32. Note that inasmuch asfingers 50 are fully retracted as they sweep past top wall 32, they donot interfere with the blade 64 such that a truly effectivecrop-stripping action is obtained at that point.

Behind the packer 46 and above the loading duct 26 is located a stuffingfork 66 for periodically sweeping an accumulated charge into the balingchamber 12 from the duct 26. The fork 66 has a transverse square tube 68spanning the duct 26 above the latter from which a series of laterallyspaced-apart, elongated tines 70 depend. The tines 70 are spaced apartin accordance with the slots 34 in the top wall 32 of duct 26 such thattines 70 may enter chamber 27 through slots 34 and move along the duct26 toward the bale case 10 during the loading cycle.

The fork 66 also includes a pair of levers 72 at opposite ends of thetube 68 that are mirror images of one another. Each lever 72 carries thetines 70 at its lower end and is rotatably coupled with a crank 74 atits upper end through a pivot 76. The cranks 74, in turn, are rigidlyaffixed to opposite ends of a drive shaft 78 that spans the bale case 10above the packer 46. Shaft 78 is, in turn, controlled by a dog clutch 79(to be described in detail below) on the left side of the bale case 10that is associated with a large sprocket 80. The sprocket 80 receivesdriving power from an endless chain 82 entrained around a drive sprocket84 carried by a drive shaft 86. In this manner, the normally upper oroperated end of each lever 72 is mounted for movement in a circular pathof travel about the axis of shaft 78.

A pair of stationary fulcrums 88 for the levers 72 extend laterallyoutwardly from opposite sides of the bale case 10 and are receivedwithin corresponding longitudinally extending slots 90 of the levers 72.Thus, during rotation of the upper ends of levers 72 by cranks 74, thefork 66 is operated through a generally kidney-shaped path of travel 92into, along and out of the duct 26, as illustrated in FIG. 4. Note thatthe path of travel 92 extends upwardly through inlet 22 and into thebaling chamber 12 for a short distance such as to assure that the chargefrom duct 26 is fully loaded into the chamber 12 during each loadingcycle. Note also that because the levers 72 are shifted along as well asturned about the fulcrums 88 during each revolution of the cranks 74(compare FIGS. 1 and 2 with FIG. 4), the fulcrum points for the levers72 are displaced accordingly. Therefore, a long lever arm is presentedbetween the pivots 76 and fulcrums 88 when the levers 72 are in thestandby positions of FIGS. 1 and 2, and a short lever arm is presentedbetween pivots 76 and fulcrums 88 when levers 72 are fully into the duct26 and illustrated in FIG. 4. Consequently, the upsweep or stuffingstroke of the fork 66 is considerably more rapid than the initial entryand final withdrawal strokes thereof. An obliquely extending leg 94 ofeach slot 90 adjacent the corresponding pivot 76 has the effect ofretarding the upsweep of the fork 66 during its initial entry into theduct 26.

Returning now to the backstop device 38 mounted on the bottom wall 36 ofduct 26 adjacent the latter's discharge end 28, such device 38 includesa series of hookshaped fingers 96 spaced along and rigid to a commonshaft 98 spanning the duct 26 behind the latter. The shaft 98 issupported by the duct 26 for rotation about its longitudinal axis so asto swing the fingers 96 into and out of the chamber 27, as illustratedbest in FIGS. 4 and 5. An operating crank 100 fixed to the right end ofshaft 98 has a tension spring 102 (FIG. 2) connected thereto for thepurpose of yieldably biasing the fingers 96 into the chamber 27. As alsoshown in FIG. 2, the operating crank 100 of the shaft 98 is mounted onthe latter intermediate the ends of the crank 100, and its end remotefrom the spring 102 is pivotally attached to a link 103 that extendsupwardly and forwardly to pivotally connect to the rear of a rocker 104.The rocker 104 is horizontally pivoted at 105 to the right side of thebale case 10 and carries a cam follower 106 at its forward end that isdisposed for engagement with and operation by an arcuate cam 108 rigidlyaffixed to the inner face of the crank 74.

The cam 108 is so positioned on the crank 74 that as soon as the crank74 begins counterclockwise rotation during activation of the stuffer 66,the follower 106 will be engaged to cause the fingers 96 to rock backout of the chamber 27 and to continue in such removed position untilsuch time as the stuffer 66 has swept the accumulated charge up into thebaling chamber 12, whereupon the spring 102 is allowed to return thefingers 96 to their position within the chamber 27.

The backstop 38 works in conjunction with a sensor 110 carried by theduct 26 somewhat adjacent the forward end 30 of the latter and more orless below the packer 46. The sensor 110 comprises a rectangular plate112 which spans the duct 26 across the bottom thereof and is attached tothe latter by pivot means 114 for movement through a short swinging arcbetween an innermost, standby position as illustrated in the figures andan outermost, operated position (not shown) against a stop 116. A crank118 on the left side of the bale case 10 is fixed to the pivot means 114for swinging movement therewith, and an upwardly and forwardly extendingmember 120 connected to the upper end of the crank 118 is yieldablybiased upwardly and forwardly by a tension spring 122 such as to urgethe plate 112 into the chamber 27 toward its standby position asillustrated.

By virtue of the backstop 38 serving to create back pressure within thechamber 27, the sensor 110 can be utilized to determine when the chargeaccumulating within chamber 27 has reached predetermined characteristicsof density and size. In this respect, the resistance which the plate 112exerts against being swung outwardly against the stop 116 determines thedensity level at which the sensor 110 will be "triggered", and ittherefore becomes essential for the operator to coordinate the tensionof spring 122 with the desired density of the charges to be stuffed intothe baling case 10. Such triggering of the sensor 110 may be used simplyto signal the operator that the desired density level has been achievedand that it is then time to manually engage the clutch 79 to activatethe stuffer 66. On the other hand, such actuation of the stuffer 66 maybe effected automatically in the manner now to be described.

Power to drive the stuffer 66 is, as earlier mentioned, derived from thedrive shaft 86 and its sprocket 84 on the left side of the bale case 10,as illustrated in FIG. 1. It is to be noted that, as illustrated inFIGS. 2 and 3, the shaft 86 is constantly rotating inasmuch as it iscoupled directly to the main drive line 124 of the machine through aflywheel 126, a right angle gearbox 128 having an output shaft 130, achain and sprocket assembly 132 that includes a very large sprocket 134,and crank and pitman assemblies 136 that reciprocate the plunger 20.Parenthetically, it should be further noted that the output shaft 130from the gearbox 128 serves to drive the packer 46 and the pickup 40through a first sprocket 138 carried by the shaft 130 on the right sideof the bale case 10 and a drive chain 140 that entrains both the firstsprocket 138 and a second sprocket 142 rigidly affixed to the shaft 52of the packer 46. A third, smaller sprocket 144 on the shaft 52 isentrained by another chain 146 that extends downwardly and forwardlyfrom the packer 46 to entrain a fourth sprocket 148 carried by a drivenshaft 150 of the pickup 40.

The angle of pull of the tension spring 122 on the member 120 is suchthat the member 120 is urged toward a laterally projecting peg 152adjacent the upper end of the member 120. When the sensor 110 is in itsstandby position, as illustrated in FIG. 1, the member 120 rides on thepeg 152. However, when the sensor 110 has been triggered against thestop 116, such action pulls the member 120 downwardly and rearwardly sothat it drops off the peg 152, as illustrated in FIG. 6, to the extentpermitted by a limit block 154. A short, angled connector 156 transmitsthis motion from the member 120 to an inverted, generally U-shapedtrigger 158 of the clutch 79 to rock the trigger 158 in a clockwisedirection about a fixed pivot 160.

Prior to actuation in this manner, the trigger 158 is positioned asillustrated in FIG. 1 wherein it may be seen that a roller 162 on adownwardly extending leg 164 is in position to engage and block one arm166 of a small bell crank 168 also forming a part of the clutch 79. Thebell crank 168 is mounted on the crank 74 by a pivot 170, and a tensionspring 172 yieldably biases the bell crank 168 in a clockwise directionviewing FIGS. 1 and 6. The opposite arm 174 of the bell crank 168carries its own roller 176 the does not interfere with rotation of ashoulder 178 on the sprocket 80 when the bell crank 168 is rocked backto its standby position, as illustrated in FIG. 1. However, when thetrigger 158 is operated by the member 120, as illustrated in FIG. 6, soas to pull the roller 162 out of the way of the arm 166 of bell crank168, the roller 176 on the bell crank arm 174 becomes disposed withinthe path of travel of the shoulder 178. Accordingly, the next time thatthe shoulder 178 comes around to the roller 176, the stuffer drive shaft78 will receive driving power from the drive line 124.

Inasmuch as it is desired to operate the stuffer 66 through but a singlestuffing stroke during each cycle, it is necessary to reset the trigger158 prior to a complete revolution of the sprocket 80. Accordingly, thecrank 74 is provided with a reset cam 180 on the end thereof remote fromthe pivot 76, such cam 180 being of arcuate configuration and beingdisposed to engage a roller 182 on the opposite leg 184 shortly afterthe crank 74 begins rotation. Once the cam 180 has engaged the roller182, further rotation of the crank 74 causes the trigger 158 to berocked counterclockwise viewing FIG. 6 so as to once again position theroller 162 in alignment with the bell crank 168 when the lattercompletes its cycle. This motion also pulls the member 120 back up ontothe peg 152 so that the sensor 110 is also reset.

OPERATION

As the baler is advanced, the pickup 40 continuously lifts crop materialfrom the ground and feeds it rearwardly into the open end 30 of the duct26 where it is packed upwardly and rearwardly into the accumulatingchamber 27 by the packer 46. Assuming that the backstop 38 is insertedfully into the chamber 27 at this time, the charge of material thatbegins to accumulate within the chamber 27 is engaged by the backstop 38such that further upward travel toward the plunger 20 is resisted. Thisalso has the effect of creating back pressure within the duct 26, andwhen that pressure reaches a predetermined level according to thedesired density of the accumulating charge, the sensor 110 will bedeflected downwardly against the stop 116 to pull the member 120 off thepeg 152 and thereby engage the clutch 79 in the manner just abovedescribed. The stuffer 66 is thereby operated through a single stuffingcycle through the sequence illustrated in FIG. 4 to load the accumulatedcharge up into the bale case 10 from the duct 26.

As the stuffer 66 begins its charging stroke, the cam 108 on the crank74 of the right side of the bale case 10 engages the follower 106 tocause the backstop 38 to be rocked back out of the chamber 27 so as toavoid interference with the up-moving charge and the forks 70. Onceclearance has been provided, the backstop 38 is reintroduced into thechamber 27 by the return spring 102 as the cam 108 rotates on past thefollower 106.

Reciprocation of the plunger 20 must be correlated with actuation of thestuffer 66 so that, regardless of the position of the plunger 20 at thetime the sensor 110 is actuated, the plunger 20 and the stuffer 66 willoperate in proper timed relationship to one another. This is achieved bythe dog clutch 79 which allows a certain amount of dwell in the stuffer66 if the plunger 20 is not in the proper position at the time thesensor 110 has been actuated. In this respect note that even though thetrigger 158 may be actuated, the clutch 79 cannot be fully engaged untilsuch time as the shoulder 178 comes around and bears against the roller176 of the bell crank 168. The timing between the shoulder 178 and theroller 176 is such that the crop-engaging face 20a of the plunger 20 isin the position designated "0°" in FIG. 4 at such point in time, thiscorresponding as well to the "0°" point for the stuffer 66 in the samefigure.

Note, then, in FIG. 4 that when the stuffer 66 is at its starting point,the plunger 20 is just barely covering the inlet 22. As the stuffer 66moves through the first 60 degrees of its travel and enters the duct 26,the plunger 20 retracts to almost fully clear the inlet 22, whereuponthe stuffer 66 moves quite guickly from 60 degrees to 150 degrees toflip the charge up into the chamber 12. Inasmuch as the plunger 20begins moving rearwardly during such motion of the stuffer 66, andinasmuch as the forks 70 project up into the chamber 12 along the pathof travel 92, the vertically slotted plunger 20 effectively wipes thecharge off the forks 70 and continues rearwardly in its compressionstroke. The stuffer then slowly returns to its originating position forthe remainder of its 360 degree cycle.

The frequency of operation of the stuffer 66 depends entirely upon howquickly the duct 26 accumulates a charge having the predetermineddesirable characteristics of size and density. If the machine isoperating at full capacity such that a full charge is ready and waitingin the duct 26 at the beginning of each new plunger cycle, then thestuffer 66 will operate non-stop. On the other hand, if the windrowbeing picked up by the machine is so light and/or uneven that theaccumulating charge does not come up to the desired parameters by thetime the stuffer 66 has completed its cycle, then one or more plungercycles may be skipped as required.

In effect, therefore, the operation of the baler may be described asincluding a check or measurement of the accumulated charge at thecompletion of each plunger cycle. If the charge is sufficiently dense,the sensor 110 will perceive this fact and either engage the clutch 79or maintain it engaged so that the next plunger cycle will beaccompanied by a stuffing cycle as well. On the other hand, if thesensor 110 perceives that the charge has not been sufficientlydensified, then it causes the stuffer 66 to skip one or more plungercycles as may be required.

ALTERNATIVE EMBODIMENTS

While the foregoing description relates to a preferred embodiment of thepresent invention, it is by no means the only possible embodimentthereof. For example, although not specifically illustrated in thefigures, it is to be understood that one alternative embodiment of thepresent invention includes clutching the stuffer 66 in the above mannerwithout stopping the plunger 20, but eliminating the use of the backstop38. In such a situation, the bottom 20b of the plunger 20 (see FIG. 4)is utilized as a backstop of sorts, albeit a moving one, inasmuch as thebottom 20b closes the inlet 22 for much of the plunger cycle. Thisarrangement has the disadvantage, however, of the face that the plungerbottom 20b cannot provide a source of back pressure for the chargeduring the time that the inlet 22 is uncovered, and, hence, thefrictional resistance of the walls of the duct 26 must be relied uponduring such times to induce back pressure. If such pressure is notsufficiently high during the time the inlet 22 is open, chances are thatwhen it once again becomes closed by the bottom 20b of the plunger 20,sufficient back pressure will arise to actuate the sensor 110 andthereby engage the clutch 79.

Another alternative embodiment is illustrated in FIGS. 7-9 which shows away of using the forks 70 as a backstop in lieu of the previouslydescribed backstop device 38. In this arrangement, the variouscomponents are practically the same as in the first embodiment, but thefulcrum point for the stuffer 66 is shifted somewhat so that the forks70 do not enter the bale case 10. Moreover, the timing of the clutch 79is changed so that the forks 70 will come to rest within the duct 26 atthe "0°" position illustrated in FIG. 7 if the clutch 79 is disengagedat the completion of a stuffing-compaction cycle. In addition, it willbe noted that the trigger 158 is positioned at the rear of the clutch 79instead of on the front side thereof as in the first embodiment. Also,the connector 156 is lengthened.

In other respects the operation of this embodiment is virtually the sameas that of the first embodiment. If the charge accumulating within thechamber 27 has obtained the desired characteristics by the time thestuffer 66 has completed its 360° movement, then the clutch 79 willremain engaged so that the stuffer 66 will operate non-stop.

On the other hand, if the desired density has not yet been achievedwithin the duct 26 by the time the stuffer 66 nears the completion ofits cycle, then the clutch 79 will be disengaged so as to leave theforks 70 positioned across the top of the duct 26, as illustrated inFIG. 7. This causes the forks 70 to serve as backstop means whereby toincrease the back pressure within the charge and thereby encourage thesensor 110 to be actuated.

It is also to be noted that the reset cam 180 on the crank 74 is movedin this particular embodiment from its position with the firstembodiment. As illustrated in FIGS. 7-9, the new position of the resetcam 180 is on that end of the crank 74 adjacent the pivot point 76, suchrelocation being necessary in view of the repositioning of the trigger158. The operation of the reset cam 180 is precisely as earlierexplained with regard to the first embodiment.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:
 1. In a machine for baling a volumeof material supplied at an irregular rate:a hollow bale case defining abaling chamber; a plunger within said chamber; means for continuouslyreciprocating said plunger to compact material delivered into thechamber; a loading duct communicating with said chamber and throughwhich a charge of material be delivered to the chamber; apparatus forcontinuously feeding material into said duct to accumulate a materialcharge of predetermined characteristics; a loader operable tosuccessively stuff charges from said duct into the chamber; means fordriving said loader in timed relation to reciprocation of the plunger;and a clutch between said driving means and the loader for the temporarydisengagement of the loader from the driving means without affecting theoperation of said plunger is a charge having said predeterminedcharacteristics fails to accumulate in said duct during the precedingstuffing cycle.
 2. In a machine as claimed in claim 1; and a sensorresponsive to the density of the accumulating charge in said duct foroperating said clutch.
 3. In a machine as claimed in claim 1, whereinsaid loader includes a fork shiftable through a closed loop of travelinto, along and out of the duct for stuffing an accumulated charge intothe chamber, said clutch being operable to terminate said travel whilethe fork remains within the duct at a position to serve as a backstopagainst which the accumulating material may be precompressed.
 4. In amachine as claimed in claim 1; a backstop within said duct in a positionagainst which the accumulating material may be precompressed; and meansfor temporarily removing said backstop from the duct in timed relationto operation of the loader.
 5. In a machine as claimed in claim 4; andmeans for returning said backstop to said position in the duct followingsaid temporary removal.
 6. In a machine as claimed in claim 5, whereinsaid backstop includes a plurality of laterally spaced fingers carriedby a common support and extending partially across the duct when in saidposition.
 7. In a machine as claimed in claim 5, wherein said means forremoving the backstop from the duct includes a cam and a cam followerdisposed for operable interengagement during operation of the loader. 8.In a machine as claimed in claim 7, wherein said means for returning thebackstop includes means yieldably biasing the backstop toward saidposition.